Self-shaping dental matrix

ABSTRACT

A thin flexible sheet insertable uprightly between teeth has a small hole at one end for receiving a pulling instrument and a compound tapering wedge at the opposite end for holding the sheet between teeth. The wedge is shaped such that it not only fixes the matrix between teeth but imparts a bend to the matrix sheet to partly surround the tooth being worked on.

United States Patent 1 [111 3,795,052

Mowery Mar. 5, 1974 SELF-SHAPING DENTAL MATRIX 2,152,877 4/1939Dagavarian 32/63 [76] Inventor: Llewellyn L. Mowery, 1214 Central,

Redands Calif. 92373 Primary ExammerLouis G. Mancene AssistantExaminer.l. Q. Lever Filed! J 1972 Attorney, Agent, or FirmWilliamJacquet Gribble [21] Appl. No.: 259,460 [57] ABSTRACT 52 US. Cl. .Q32/63 A thin flexible Sheet insertable uprightly between 5 A61c 5/12teeth has a small hole at one end for receiving a pull- [58] Field ofSearch 32/63 ing instrument and a Compound tapering wedge at theopposite end for holding the sheet between teeth. The 5 R f Cited wedgeis shaped such that it not only fixes the matrix UNITED STATES PATENTSbetween teeth but imparts a bend to the matrix sheet to partly surroundthe tooth being worked on. 3,108,377 10/1963 Meyer 32/63 2,891,3136/1959 Crowley 32/63 3 Claims, 7 Drawing Figures SELF-SHAPING DENTALMATRIX BACKGROUND OF THE INVENTION The invention relates to dentalmatrices for forming a wall between teeth being filled and moreparticularly to such matrices capable of fabrication at such low cost asto be disposable. The general field of the device is shown by US. Pat.No. 3,636,631 entitled Teeth- Separating Wedges For Use During DrillingOperations, issued Feb. 1, 1972 to Benjamin F. Tofflemire.

Frequently teeth deteriorate in the contact area between teeth. In ordersuccessfully to repair the deteriorated area the tooth must be drilledout to eliminate the decayed material and to form a retaining socket forthe filling amalgam. It is desirable during the filling operation toseparate the teeth in the manner illustrated by the Tofflemire patent.It is also desirable to shield the adjacent tooth from the fillingmaterial by a matrix wall. The invention therefore is aimed at providinga self-shaping dentral matrix which not only separates adjacent teethbut forms an enveloping wall in the situs of the filling. Preferablysuch matrices should be so low in fabrication cost that re-use is noteconomically required and thus eliminate the necessity forexpensivematrix sterilization and re-use.

SUMMARY OF THE INVENTION The invention contemplates a disposableself-shaping dental matrix which comprises a flexible strip, which maybe metallic, with attachment means on the strip for receiving a tool,and wedge means on the strip. The wedge means may be both an anchoringelement and a contouring means for the strip. Preferably the wedge andcontouring means is a protuberance applied to the strip and diminishingin mutually perpendicular directions from a corner of the strip oppositethe attachment means. An alternate embodiment of the inventioncontemplates the protuberance as a .hollow convexity in the face of thestrip which may be formed by stamping.

By utilizing stainless steel strips on the order of 0.00 1 -inchthickness to which a plastic material may be applied to form theprotuberance, the matrices may be not only self-shaping but alsodisposable. By using a simple aperture opposite the wedge protuberance,a conventional elongate dental tool may be used as an attachment devicefor drawing the matrix between teeth.

These and other advantages of the invention are apparent from thefollowing detailed description and drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a schematic plan view of theteeth of the lower jaw with matrices between adjacent teeth;

FIG. 2 is an elevational view of two adjacent teeth separated by amatrix in accordance with the invention;

FIG. 3 is an elevational view of a preferred matrix of the invention;

FIG. 4 is a plan view of the matrix of FIG. 3;

FIG. 5 is an end elevation of the matrix of FIG. 3;

FIG. 6 is a sectional elevation taken along line 6--6 of FIG. 4; and

FIG. 7 is a sectional elevation similar to FIG. 6 of a further alternateembodiment of the invention.

In the various Figures like reference characters are used for likeparts.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 the incisors 10 ofthe lower jaw and the ca nines 11 are schematically illustrated, as arethe bicuspids 12, the molars 13 and the wisdom teeth 14. A matrix 16 inaccordance with the invention is shown drawn into place between bicuspidl2 and molar 13 by a schematically represented dental tool 18. A secondmatrix 19 in accordance with the invention is shown between the twobicuspids 12. A filling situs 21 is shown in molar 13 adjacent thematrix. The matrix comprises a strip 22 which may be a stainless steelband with a thickness of 0.001 inch with a compound tapering wedge 24.As the tool 18 pulls the matrix between the teeth, the strip tends tobecome concave (n the side with the wedge and thus forms a wall whichpartially surrounds the situs 21 of the filling.

The approximate vertical orientation of the matrix 16 is shown in FIG. 2with the contact between the wedge 24 and the tooth 13 beingillustrated.

Matrix 19 of FIG. I is shown prior to its final location between theteeth with its wedge 24 not yet in contact with the bicuspid 12. Thematrix may be easily manipulated by a device such as dental tool 18 forremoval once its function at the situs of the filling is fulfilled.

In FIGS. 3-6 a matrix 27 comprises a strip 28 which may be of anyresiliently flexible material such as metal or plastic. The strip has acircular aperture 29 at one upper corner which serves as an attachmentmeans to the tool used to manipulate it within the mouth. The wedge 24,as can be seen from FIGS. 3, 4 and 5, is fuller near its outer bottomedge 31. The projection of the wedge from the strip diminishesvertically to coincidence with the plane of the strip at upper point 32,and horizontally to coincidence at lower point 33. While the transitionlines between the various full and thin projections of the wedge fromthe surface of the strip have been shown as curving, the invention doesnot preclude straight line warped surfaces for the wedge. Epoxymaterials and others, like substances that become solid but plastic uponfinal setting to accommo date the bending ofthe matrix strip, may beused to form the protuberance. The wedge 24 of the embodiment of FIG. 3has proven to'be effective not only to secure the matrix between teeth,but also to induce shaping the strip into a concave wall between theteeth adjacent the filling situs.

The alternate embodiment of FIG. 7 has a flexible strip 28 and a convexwedge 35 which has a hollow 36. The wedge 35 protrudes beyond the planeof strip 28 in the same manner as the wedge 24 of the previouslydescribed embodiment. However, the wedge is formed, as by stamping, fromthe material of the matrix and both the wedge and the attachment meanshold, such as the hole 29 of FIG; 3, may be formed in a single stampingoperation when the matrix is formed from a continuous strip of material.

The illustrative embodiments show the utility and ease of application ofthe matrix within the mouth of a patient. The matrix not only givespartial separation to adjacent teeth at the situs of the filling buteffects a wall to contain the fill material until it hardens.

In view of the disclosure herein, variations within the scope of theinvention other than those shown herein .will occur to those skilled inthis particular art. It is therefore desired that the invention bemeasuredby the appended claims, rather than by the illustrativecmbodiments .digzlosed herein.

I claim? 1. A disp'osable dental matrix comprising a flexible strip,attachment means on the strip located near a cornet of said strip, atapering protuberance on the strip diminishing in mutually perpendiculardirections from a corner of the strip opposite to the attachment means Iso protuberance comprises a hollow convexity in the face of the strip.

1. A disposable dental matrix comprising a flexible strip, attachmentmeans on the strip located near a corner of said strip, a taperingprotuberance on the strip diminishing in mutually perpendiculardirections from a corner of the strip opposite to the attachment meansto a point at a longitudinal edge of the flexible strip near themidpoint of said edge.
 2. A matrix in accordance with claim 1 whereinthe protuberance comprises an area of solid plastic material affixed tothe strip.
 3. A matrix in accordance with claiM 1 wherein theprotuberance comprises a hollow convexity in the face of the strip.